This card works very well with "Dragunity Phalanx" and "Dragunity Dux"/"Dragunity Legionnaire". Normal Summon "Dux" or "Legionnaire" to equip Phalanx from the grave, then Special Summon Phalanx with its effect. Then you can send Phalanx to the graveyard to Special Summon "Dragunity Arma Mystletainn" from your hand, then you may equip "Dragunity Phalanx" from the grave once again or choose another monster to equip from the grave to "Mystletainn".

If you have a 2nd "Dragunity Arma Mystletainn" you can repeat this combo by equipping "Dragunity Phalanx" to the first "Dragunity Arma Mystletainn", Special Summoning it, then send it to the grave to Special Summon the 2nd "Dragunity Arma Mystletainn" from your hand as well.

Normal Summon "Dragunity Brandistock" and send it to the Graveyard to Special Summon this card. Then equip "Dragunity Brandistock" to this card with its effect so it can attack twice each turn.

Normal Summon "Debris Dragon" and Special Summon "Dragunity Phalanx" from the Graveyard with "Debris'" effect, then send "Phalanx" to the Graveyard to Special Summon "Dragunity Arma Mystletainn", tune it with "Debris" for an easy "Trident Dragion".

Normal Summon "Dragunity Legionnaire" and equip a monster with his effect from the graveyard, activate his effect to destroy 1 monster on the field by sending a Dragunity equip monster to the graveyard, then tribute "Dragunity Legionnaire" to the grave to Special Summon "Dragunity Arma Mystletainn" from your hand and equip another monster.

If you equip "Dragunity Phalanx" to this card, you can Special Summon "Dragunity Phalanx" with its own effect and Synchro Summon any level 8 Synchro Monster.

"Dragunity Tribus" can send any level 3 or lower Dragon-Type Dragunity monster to the Graveyard that can be equipped to this card.

You can combine with the above combo and send "Dragunity Phalanx" to the graveyard with the effect of "Dragunity Tribus" then tribute "Dragunity Tribus" to Special Summon "Dragunity Arma Mystletainn" and equip "Dragunity Phalanx" to then Synchro Summon a level 8 Synchro Monster.

Summon "Dragunity Phalanx", then send it to the Graveyard to Summon this card out. You can now get "Dragunity Phalanx" back, and Synchro Summon for level 8 Synchro Monster, using only 2 cards in your hand.

This card can be a decent replacement or addition of "Dragunity Knight - Vajrayana" (although without its ATK-doubling effect, but with better starting ATK).

Even better, if your "Dragunity Dux" is having its effect negated by "Effect Veiler", you can send Dux to the Graveyard and Special Summon this card, then if you were trying to equip "Dragunity Phalanx", you can do the same with Mystletainn and keep going. The good point is, as soon as you Summon this card and "Phalanx" successfully, you can just Synchro Summon level 8 monster as normal without going through "Dragunity Knight - Vajrayana" in your Extra Deck.